diff --git a/Cargo.lock b/Cargo.lock
index 94dc996ec84..325a19210d9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -47,6 +47,11 @@ dependencies = [
  "nodrop 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "arrayvec"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "atty"
 version = "0.2.13"
@@ -739,79 +744,79 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_arena"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_ast"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_index 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_lexer 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_macros 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_index 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_lexer 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_macros 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "scoped-tls 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_ast_passes"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_attr 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_parse 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_attr 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_parse 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_ast_pretty"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_target 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_target 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_attr"
-version = "669.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_macros 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+version = "671.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_macros 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_data_structures"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -826,9 +831,9 @@ dependencies = [
  "measureme 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "once_cell 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_graphviz 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_index 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_graphviz 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_index 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-hash 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon-core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -840,15 +845,15 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_errors"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "annotate-snippets 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "atty 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "termcolor 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "termize 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-width 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -857,57 +862,57 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_expand"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_passes 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_attr 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_lexer 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_parse 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_passes 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_attr 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_lexer 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_parse 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_feature"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_fs_util"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rustc-ap-rustc_graphviz"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rustc-ap-rustc_index"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "smallvec 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "arrayvec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_lexer"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -915,7 +920,7 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_macros"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -926,25 +931,25 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_parse"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_lexer 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_lexer 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-normalization 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_serialize"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "indexmap 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -953,36 +958,36 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_session"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.21 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_fs_util 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_target 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_fs_util 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_target 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rustc-ap-rustc_span"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "md-5 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_arena 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_index 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_macros 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_arena 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_index 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_macros 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "scoped-tls 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "sha-1 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-width 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -990,16 +995,16 @@ dependencies = [
 
 [[package]]
 name = "rustc-ap-rustc_target"
-version = "669.0.0"
+version = "671.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_index 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_macros 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_index 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_macros 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1058,7 +1063,7 @@ dependencies = [
 
 [[package]]
 name = "rustfmt-nightly"
-version = "1.4.19"
+version = "1.4.20"
 dependencies = [
  "annotate-snippets 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "anyhow 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1074,15 +1079,15 @@ dependencies = [
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_attr 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_expand 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_parse 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_attr 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_expand 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_parse 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-workspace-hack 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustfmt-config_proc_macro 0.2.0",
  "serde 1.0.101 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1435,6 +1440,7 @@ dependencies = [
 "checksum anyhow 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)" = "9267dff192e68f3399525901e709a48c1d3982c9c072fa32f2127a0cb0babf14"
 "checksum arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "0d382e583f07208808f6b1249e60848879ba3543f57c32277bf52d69c2f0f0ee"
 "checksum arrayvec 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "cd9fd44efafa8690358b7408d253adf110036b88f55672a933f01d616ad9b1b9"
+"checksum arrayvec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cff77d8686867eceff3105329d4698d96c2391c176d5d03adc90c7389162b5b8"
 "checksum atty 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)" = "1803c647a3ec87095e7ae7acfca019e98de5ec9a7d01343f611cf3152ed71a90"
 "checksum autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
 "checksum backtrace 0.3.40 (registry+https://github.com/rust-lang/crates.io-index)" = "924c76597f0d9ca25d762c25a4d369d51267536465dc5064bdf0eb073ed477ea"
@@ -1517,25 +1523,25 @@ dependencies = [
 "checksum regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dc220bd33bdce8f093101afe22a037b8eb0e5af33592e6a9caafff0d4cb81cbd"
 "checksum regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)" = "11a7e20d1cce64ef2fed88b66d347f88bd9babb82845b2b858f3edbf59a4f716"
 "checksum rust-argon2 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4ca4eaef519b494d1f2848fc602d18816fed808a981aedf4f1f00ceb7c9d32cf"
-"checksum rustc-ap-rustc_arena 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c9cdd301e9dcb15ead384fc07196c850fd22829fae81d296b2ed6b4b10bf3278"
-"checksum rustc-ap-rustc_ast 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3f7c0d0537ca69dfe4a49212035295dfb37a235b5df01aa877d50b247f4775b8"
-"checksum rustc-ap-rustc_ast_passes 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d4cf4dca95f55f70eeb193fb08554026d79d0628de771fd726bb609e36887b82"
-"checksum rustc-ap-rustc_ast_pretty 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "202bd2886d0cfa48baa3711042c14843f1b4852555b7ee7e5376bf66b276cb8d"
-"checksum rustc-ap-rustc_attr 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b11ee1d92b3214e8a8c7829eff84cc1b03925da0ea5c6900cefe05b99edb4682"
-"checksum rustc-ap-rustc_data_structures 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a45d43b974d4cb9e32e5a15119c5eb7672c306ef09b064f2125b6a0399f6656"
-"checksum rustc-ap-rustc_errors 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8cd895d440820aaa04e6dc5486105494920a1e9779b9b051e8dba4ca5c182f94"
-"checksum rustc-ap-rustc_expand 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "71a0cc7820860d6691bf0aa7a95cdbc60f6587b495c18e0fa15a888fdabbf171"
-"checksum rustc-ap-rustc_feature 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5473d5106401aa46f881eb91772f0a41fd5f28ae6134cf4b450eb1370ea6af22"
-"checksum rustc-ap-rustc_fs_util 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8da1d57ee7a7ef55f31a97d99c7f919f02fc9a60ab96faa8cf45a7ae3ab1ccbf"
-"checksum rustc-ap-rustc_graphviz 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e3af62b20460908378cd1d354917acd9553376c5363bbb4e465f949bd82bdef9"
-"checksum rustc-ap-rustc_index 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3af7d4c456fe7647453d3fcd58335c9d512d1ff9a239a370b7ebdd353d69f66f"
-"checksum rustc-ap-rustc_lexer 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "456af5f09c006cf6c22c1a433ee0232c4bb74bdc6c647a010166a47c94ed2a63"
-"checksum rustc-ap-rustc_macros 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "64f6acd192f313047759a346b892998b626466b93fe04f415da5f38906bb3b4c"
-"checksum rustc-ap-rustc_parse 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c006e8117c1c55e42bb56386c86ce6f7e4b47349e0bec7888c1d24784272e61b"
-"checksum rustc-ap-rustc_serialize 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "306ced69beaeebe4de9552ee751eb54ea25b5f34a73fe80f5f9cbbe15ccebc48"
-"checksum rustc-ap-rustc_session 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "dbff48435f5a476365e3ab5f49e07f98715cecb2d8c5bbcafeaf3aec638407be"
-"checksum rustc-ap-rustc_span 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ec4273af0abbe78fc4585316ab193445c848c555e9203ddc28af02330918bf30"
-"checksum rustc-ap-rustc_target 669.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6f9a2d6004ce6ad492a8eeacc2569b1c008169434b8828996d8dade4e5c6b6ee"
+"checksum rustc-ap-rustc_arena 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4a3941333c39ffa778611a34692244052fc9ba0f6b02dcf019c8d24925707dd6"
+"checksum rustc-ap-rustc_ast 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "27c579f7d89e6fc971b433e92bb2b8c65b716d7c797b21de8685945be9455610"
+"checksum rustc-ap-rustc_ast_passes 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f9914fadee461568d19ca2ebaec8699ff898f8ffec9928154659a57ee018e5fd"
+"checksum rustc-ap-rustc_ast_pretty 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2a78c5cc50a2f294d3c4e9131a15676724c9f136d3ed54e9ba419850b6025cb3"
+"checksum rustc-ap-rustc_attr 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a78ce08227d146949755175c0cf710280a4b5bf6ee504c0e3f7ccc30d66fbfd9"
+"checksum rustc-ap-rustc_data_structures 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9d5ac3735c38d2d0e95991ebcd7eb1618b60e784194a738e0ce2e8d39c39b809"
+"checksum rustc-ap-rustc_errors 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5166a95afa6e3b78ccbece4c2f1e163634854297f1147c6fd90e2712ed3fede5"
+"checksum rustc-ap-rustc_expand 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1a0586e83bdfe70eda8393429a8a38ecb529525dd252d787e479af075d3cab08"
+"checksum rustc-ap-rustc_feature 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "48fc3aa8de0737a8c5a4353e6948548f469150d2b5d3eac391843de32c6c6ca2"
+"checksum rustc-ap-rustc_fs_util 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "59fd3380f4029020b693bbfd5a14ec8c893ec33c5c0063ad2e68e46d3fbd6a1f"
+"checksum rustc-ap-rustc_graphviz 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b54bd98f70e04291bf611151d1fcd4d7770b35f7ec603d301c4aee0d1979cca4"
+"checksum rustc-ap-rustc_index 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "335bfb187a2489a59ee8c67fcf5d1760e9dcdbe0f02025c199a74caa05096b15"
+"checksum rustc-ap-rustc_lexer 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "22e1221f3bfa2943c942cf8da319ab2346887f8757778c29c7f1822cd27b521f"
+"checksum rustc-ap-rustc_macros 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8b774df26c4ef513555b3a303cb209f44cf68a9e6a5481b41ac832301c6487cb"
+"checksum rustc-ap-rustc_parse 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "065e632101bdd57a271f38ee7a4d72b5a3d0467ec845104346c284b2c6c69960"
+"checksum rustc-ap-rustc_serialize 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0e8c0b704e3dedb97cbb1ac566bbc0ab397ec4a4743098326a8f2230463fd9f9"
+"checksum rustc-ap-rustc_session 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "dda99ede4e6e260712754f8548b0a175b615686ad393653a3bd11f6c5e41a04e"
+"checksum rustc-ap-rustc_span 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "53453791c2c0b501a921927ce8e305a801eef130920873f8da92d83dad595236"
+"checksum rustc-ap-rustc_target 671.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac82006fdb31ef44e24e1623f8b72ac2b404ef15ba20b7ebec0df35e5d20bbef"
 "checksum rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "4c691c0e608126e00913e33f0ccf3727d5fc84573623b8d65b2df340b5201783"
 "checksum rustc-hash 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
 "checksum rustc-rayon 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f32767f90d938f1b7199a174ef249ae1924f6e5bbdb9d112fea141e016f25b3a"
diff --git a/Cargo.toml b/Cargo.toml
index f55b91df032..6caf337e9ec 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 
 name = "rustfmt-nightly"
-version = "1.4.19"
+version = "1.4.20"
 authors = ["Nicholas Cameron <ncameron@mozilla.com>", "The Rustfmt developers"]
 description = "Tool to find and fix Rust formatting issues"
 repository = "https://github.com/rust-lang/rustfmt"
@@ -66,36 +66,36 @@ rustc-workspace-hack = "1.0.0"
 
 [dependencies.rustc_ast]
 package = "rustc-ap-rustc_ast"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_ast_pretty]
 package = "rustc-ap-rustc_ast_pretty"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_attr]
 package = "rustc-ap-rustc_attr"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_data_structures]
 package = "rustc-ap-rustc_data_structures"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_errors]
 package = "rustc-ap-rustc_errors"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_expand]
 package = "rustc-ap-rustc_expand"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_parse]
 package = "rustc-ap-rustc_parse"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_session]
 package = "rustc-ap-rustc_session"
-version = "669.0.0"
+version = "671.0.0"
 
 [dependencies.rustc_span]
 package = "rustc-ap-rustc_span"
-version = "669.0.0"
+version = "671.0.0"